how did so many unrelated languages around the world come to have essentially identical systems of communication?

Question

Such as very similar or near-identical vocabularies, phrases, greetings, yes/no/maybe, exclamations etc.

In: Culture

Answer 1

Different languages don’t have essentially identical systems of communication.

For example, you mention “yes/no/maybe”. Did you know that some languages don’t have words for yes and no? For example Irish and Chinese.

There are other languages that have more yes/no words than English. For example, in German both “ja” and “doch” can be translated as “yes” in English, but “ja” is only used in response to positively phrased questions (“Do you do this?”), while “doch” is only used in response to negatively phrased questions (“Don’t you do this?”).